Certain oxazolidinones and their preparation



United States Patent 3,231,578 CERTAIN OXAZOLIDINONES AND THEE PREPARATION George E. Ham, Lake Jackson, Tex., assignor to The Dow Chemical Company, Midland, Mich, a corporation of Delaware No Drawing. Filed Aug. 21, 1963, Ser. No. 303,651 12 Claims. (Cl. 260-307) This invention relates to oxazolidinones having the formula wherein each R, R and R" are H or hydrocarbon.

The above compounds are typically colorless liquids of very low volatility and can be distilled only under vacuum. They are readily hydrolyzed in aqueous acid or base to produce mixtures of alcohol, amine and carbon dioxide. They are useful as fungicides, especially in inhibiting the growth of mildew on leather, fabrics and other susceptible materials.

The compounds of the invention are conveniently made by the catalytic rearrangement-condensation of the appropriate oxazoline:

OCHR' wherein R, R and R" have the same significance as in the first formula above. In this reaction two molecules of the oxazoline are condensed to produce one molecule of the oxazolidinone.

The rearrangement is effected by contacting the oxazoline with an alkyl halide at a temperature of about 25- 200 C. The halide is preferably a primary alkyl bromide or iodide having 1-15 carbon atoms, such as, for instance, methyl iodide, ethyl iodide, butyl bromide, octyl bromide, decyl iodide, dodecyl iodide or pentadecyl bromide,

The preferred oxazolines are those wherein at least one, and preferably both of R and R" are hydrogen and R is a lower alkyl radical, i.e., an alkyl radical containing up to 4 carbon atoms.

The reaction is preferably conducted in an inert solvent, though this is not essential. Suitable solvents include the aliphatic nitriles, ketones, halohydrocarbons, ethers, sulfoxides and the lower N,N-dialky1 fatty acid amides. Among such solvents are acetonitrile, diethyl ether, acetone, chloroform, ethylene chloride, dimethyl sulfoxide, N,N-dimethylformamide, ethylene glycol dimethyl ether and the like.

In carrying out the process of the invention, the oxazoline, with or without a solvent, is mixed with a catalytic amount, suitably about 125% by weight, of the catalyst and the mixture is then maintained at the reaction temperature until substantial rearrangement has occurred. The oxazolidinone is then separated from the reaction mixture and any unreacted oxazoline, together with any recovered catalyst, is recycled to the process. The time required for the reaction varies widely, depending on the reactivity of the particular materials being used, concentration and the reaction temperature. Best results are usually obtained by use of long reaction times at moderate temperatures, such as several hours at 50-150" C.

The practice of the invention is illustrated by the following example.

A mixture of g. of 2-ethoxy-2-oxazoline, 1.93 g. of ethyl iodide and 100 ml. of acetonitrile was refluxed (80 C.) for 9 days. The solvent was then removed under 3,231,578 Patented Jan. 25, 1966 reduced pressure and the residue distilled under 0.2 mm. pressure. There was thus obtained 1.11 g. (11.1% yield) of the oxazolidinone having the formula '0 (EH5 (HIP-CH2 CgHgO-C-N-CHzCHrN It distilled at 156-164" C./0.2 mm. as a clear, viscous liquid. Its structure was confirmed by infrared analysis, and nuclear magnetic resonance analysis.

The compounds of the invention are useful as bactericides and fungicides.

When a dilute solution of the above product was crossstreaked with an inoculum of E. coli on an agar plate and the plate was then incubated until an abundant growth of E. 0011' had developed, it was noted that the areas treated with the oxazolidinone were free of such bacteria.

When an ether solution of the above product is sprayed on leather, fabrics, upholstery or other surfaces in a humid atmosphere and subject to attack by mildew, the sprayed areas are free of mildew growth while adjacent unsprayed areas support a heavy growth of mildew.

Other oxazolines as above defined can be isomerized to the corresponding oxazolidinones by heating with an alkyl halide as shown above. Suitable oxazolines inolude 2-methoxy-, 2-propoxy-, 2-isobutoxy-2-hutoxy-, 2-allyloxy-, 2-(2-methallyloxy)-, 2-benzyloxyand 2-(2-phenethoxy)-2-oxzolines and the corresponding Z-substituted- 2-oxazolines having a lower alkly radical in the 4- or 5- position or both the 4 and 5-position on the oxazoline ring. The products have properties and uses similar to those of the above product.

I claim:

1. A compound having the formula wherein R, R and R" are radicals selected from the group consisting of hydrogen and lower alkyl radicals. 2. A compound as defined in claim 1 wherein R and R" are hydrogens.

3. The compund having the formula 4. The process for making an oxazolidinone having the formula 0 E0112 1?. R" CHRC|JHR comprising condensing an oxazoline having the formula N-CHR RCHz-OC O-CHR where in the above formulas R, R and R" are radicals selected from the group consisting of hydrogen and lower alkyl radicals, said condensation being effected by contacting the oxazoline with a catalytic amount of an alkyl halide wherein the halogen has an atomic number of 35-53 and separating from the reaction mixture the thus formed oxazolidinone having the above formula.

5. The process of claim 4 wherein R and R are hydrogen.

6. The process of claim 4 wherein the catalyst is an alkyl iodide.

7. The process of claim 4 wherein the temperature is 50150 C.

8. The process of claim 4 wherein R and R are hydrogen, the alkyl halide is an alkyl iodide containing not more than 15 carbon aotrns, the temperature is 25- 200 C. and the reaction time is 1-10 days.

9. The process of claim 8 wherein R is C H 10. The process for making the oxazolidinone having the formula 4 comprising condensing the oxazoline having the formula O-CH:

by contacting the oxazoline with ethyl iodide in an inert solvent at a temperature of 50150 for a time of 1-10 days and separating from the reaction mixture the thus formed said oxazolidinone.

11. The process of claim 10 wherein the solvent is acetonitrile.

12. The process of claim 10 wherein the amount of ethyl iodide used is 125% by weight of the. amount of oxazoline.

No references cited.

NICHOLAS S. RIZZO, Primary Examiner. 

1. A COMPOUND HAVING THE FORMULA
 4. THE PROCESS FOR MAKING AN OXAZOLIDINONE HAVING THE FORMULA 